The present invention relates to a fixing device for fixing a dispensing unit on a container neck defining an external wall. This type of fixing device, frequently used in the field of perfumery, cosmetics or even pharmacy, generally comprises a fixing ring forming receiving means for holding a dispensing unit such as a pump of a valve, and a skirt, the internal wall of which is intended to engage with the external wall of the container neck.
A currently used technique consists in providing the internal wall of the skirt with one or more locking profiles which are accommodated under a shoulder formed by the external wall of the neck. These locking profiles may have the shape of snap-on heads positioned at the lower end of separate tabs; in this case, the skirt is slit in order to form tabs with the snap-on heads at their lower end. According to another technique, the snap-on profiles may assume the shape of a continuous internal peripheral fillet which protrudes inwards on the internal wall of the skirt. This fillet, like the snap-on heads, should, when mounting the ring on the neck of the container, pass over a thickened or reinforced edge of the neck below which is formed the shoulder with which the fillet or the heads cooperate. Consequently, the skirt momentarily (upon passing over the thickened edge) undergoes an outward radial deformation which increases its external diameter.
On the other hand, this type of fixing device also comprises a cladding hoop which will cover the ring, and more particularly the skirt, for an aesthetical, but also occasionally functional purpose. This is particularly the case when the skirt is made with separate tabs forming the internal snap-on heads. The hoop which will cover the skirt is then used as a blocking means in order to block the snap-on heads under the shoulder of the thickened edge of the neck.
The hoop cannot be mounted on the ring before the ring is mounted on the neck, since, as mentioned above, the tabs undergo a radial deformation outwards upon passing over the reinforced edge of the neck. By premounting the hoop on the ring, this outward radial deformation would not be possible without deforming or damaging the cladding hoop. Consequently, in this technique using tabs with snap-on heads, the hoop is only mounted on the ring as soon as the ring is mounted on the neck of the container.
In the other technique using an internal peripheral fillet, the skirt is also locally and momentarily radially deformed outwards upon passing over the reinforced edge. Consequently, neither it is possible to mount a cladding hoop on the ring; actually, in most cases, the cladding hoop is mounted on the ring, and more particularly on its skirt, through radial tightening from the tight contact between the internal wall of the hoop and the external wall of the ring. Consequently, the slightest deformation of the external wall of the skirt has the effect of deforming the hoop which is in tight contact with the skirt. Consequently, the hoop cannot be pre-mounted on the ring before mounting the ring on the neck, even with the continuous fillet technique. However, it may noted that the cladding hoop does not fulfil any function other than an aesthetical one in its fixing on the neck of the container with the technique of the continuous fillet which is itself sufficient for fixing the ring on the neck.
The problem of the premounting of the hoop on the ring provided with a continuous fillet was partly solved in document WO99/20401. In this document, a fixing device is described, comprising a cladding hoop and a fixing ring. The ring forms a skirt defining an internal wall provided with several locking profiles localized, distributed on the internal wall of the skirt. So this has nothing to do with a continuous fillet. However the skirt is not slit. To enable these point locking profiles to be radially deformed outwards upon passing over the thickened edge of the neck, corresponding neckings are provided, formed on the external wall of the skirt. Therefore, the skirt is not in contact with the internal wall of the hoop, but on the contrary defines several intermediate areas distributed on the external periphery of the skirt, at right angles to each locking profile, respectively, in order to allow a radial outward deformation of the skirt in these intermediate spaces without deforming or damaging the premounted cladding hoop. Indeed, in this document, the hoop is intended to be mounted on the ring before mounting the ring on the neck as the skirt may be radially deformed outwards in the intermediate spaces without deforming the hoop.
However, in this document the cladding hoop is provided in contact with the ring and more particularly with the skirt over the whole of its height, including the level where the skirt is in contact with the neck of the container. More specifically, between each intermediate space corresponding to a locking profile of the internal wall of the skirt, respectively, the external wall of the skirt is in tight contact with the internal wall of the hoop. Consequently, even if the skirt may be deformed radially outwards in the intermediate spaces, the fact remains at the least that the skirt is also deformed, even to a residual extent, at the level where the skirt is in tight contact with the hoop. As a result, the hoop is then slightly deformed, which leads to the very well known phenomenon of the deterioration or alteration of the cladding hoop""s surface quality, especially in the case when the hoop is made in metal which is nearly always the case. This surface alteration phenomenon occurs as a flaking known as checking. This checking phenomenon is a very widespread problem and difficult to control on metal cladding hoops. Indeed, at the slightest deformation of the hoop, this checking phenomenon occurs at its external surface and obviously spoils its aesthetical appearance. In the case of the aforementioned prior art document, in which the hoop is in tight contact over the whole of the height of the ring, it is inevitable that the hoop is slightly deformed because of this radial tightening which tends to make it expand and thus causes the occurrence of this checking phenomenon.
The object of the present invention is to find a remedy to these aforementioned drawbacks of the prior art by defining a fixing device with a cladding hoop and fixing ring, the cladding hoop of which does not undergo any substantial deformation which may cause the occurrence of this checking phenomenon, and this, while ensuring perfect fixing of the ring on the neck and of the hoop on the ring.
This object is achieved according to the invention by a fixing device for fixing a dispensing unit on a container neck defining an external wall, wherein said device comprises a cladding hoop defining an internal wall, and a fixing ring forms receiving means for holding the dispensing unit and a skirt defining an internal wall, an external wall and a free lower end, wherein said skirt further defines a first fixing area at which its internal wall is intended to engage with the external wall of the neck and a second locking area at which its external wall tightly engages with the internal wall of the cladding hoop, characterized in that the second locking area is located below the first fixing area, substantially at the lower end of the skirt.
Advantageously, an intermediate free space is formed between the skirt and the hoop at the first fixing area. Preferably, said intermediate space extends over the whole of the height of the skirt except at the second locking area. Thus, the cladding hoop is only in tight contact with the ring at the second locking area which is located at the free lower end of the skirt. Indeed, as this lower end of the skirt is free, it has less stiffness and support than its upper end connected to other portions of the ring. Therefore, this lower end is more easily deformable upon its radial tightening with the internal wall of the hoop. Further it should be noted that the locking of the hoop on the skirt only occurs at the end of the mounting operation, as the second locking area is located at the lower end of the skirt. Thus, the hoop does not undergo any type of contact elsewhere except in the area located at the height of the second locking area, which is advantageously placed at a height of the skirt which is the most able to deform plastically. Thus, the hoop cannot be deteriorated by a checking phenomenon, since, over the major portion of its height, it is not in contact with the ring, and is separated by an intermediate free space, and at the level where it is locked on the skirt, it is the latter which undergoes the radial inward deformation in order to generate the tight contact with the hoop. Thus, any deterioration by the checking phenomenon is prevented.
According to an embodiment, the second locking area has a greater external diameter than that of the first fixing area. Advantageously, an external outward shoulder connects the first area to the second area. The external wall of the skirt which advantageously forms the external wall of the ring, may thus comprise two cylindrical, advantageously circular, sections connected through an advantageously oblique shoulder, wherein the first cylindrical section extends on the major portion of the height of the skirt and has a smaller diameter than the second section which may also be cylindrical and circular and which is located at the lower end of the skirt.
According to another feature of the invention, the second locking area has a greater internal diameter than that of the first fixing area. Advantageously, an internal outward shoulder connects the first area to the second area. Thus, the internal wall of the skirt at the second locking area may serve as a guiding wall to facilitate the placing and fitting of the ring on the neck of the container. Preferably, the internal diameter of the ring at the second locking area is greater than the external diameter of the neck so that there is no tight contact between the second locking area and the neck after mounting the ring on the neck. Furthermore, the internal shoulder which is advantageously inclined, serves as convergency wall for guiding the neck up into the first fixing area of the skirt.
According to a feature of the invention, the external wall of the skirt at the second locking area is provided with deformable locking profiles against the internal wall of the hoop. In this case, the internal wall of the hoop may be in localized contact with the second locking area at the deformable locking profiles. Alternatively, the internal wall of the hoop is in continuous contact with the second locking area over the whole periphery. The external wall of the skirt at the second locking area may therefore be perfectly cylindrical, circular and smooth, or even be cylindrical, circular, but provided with a surface condition, for example as horizontal or vertical ribs or grooves, which promotes locking of the hoop.
According to another aspect of the invention, the internal wall of the skirt at the first fixing area is substantially cylindrical and has, before its mounting on the neck, an smaller internal diameter than the external diameter of the neck, so as to provide fixing through radial tightening. The wall of the skirt may be perfectly cylindrical, circular and smooth. Alternatively, the internal wall of the skirt at the first fixing area is provided with fixing profiles adapted for deformation against the external wall of the neck. Advantageously, the internal wall of the skirt at the first fixing area may be provided with blocking profiles adapted for accommodation under a shoulder inwards formed by the external wall of the neck. Anyway, whatever the profile of the internal wall of the skirt at the fist fixing area, the skirt may be radially deformed outwards in the intermediate free space without contacting or deteriorating the cladding hoop.
According to a practical embodiment, the cladding hoop comprises a cylindrical body inwardly defining the internal wall, wherein said body defines a lower end extending at least up to the free lower end of the skirt and an upper end forming a re-entering flap, wherein the hoop is only in contact with the ring at the second locking area and at the re-entering flap, the intermediate space extending between the second locking area and the re-entering flap. Thus, the hoop is fixed at its lower end through radial tightening and blocked at its lower end by the re-entering flap in abutment contact on the ring. Between these two ends, the hoop is not in contact with the ring.